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A Compensation Controller Based on a Nonlinear Wavelet Neural Network for Continuous Material Processing Operations

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Computers, Materials & Continua 2019年第7期61卷 379-397页

作者： Chen Shen Youping Chen bing Chen Jingming xie School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhanChina

Continuous material processing operations like printing and textiles manufacturing are conducted under highly variable conditions due to changes in the environment and/or in the materials being *** such,the processing parameters require robust real-time adjustment appropriate to the conditions of a nonlinear *** paper addresses this issue by presenting a hybrid feedforward-feedback nonlinear model predictive controller for continuous material processing *** adaptive feedback control strategy of the controller augments the standard feedforward control to ensure improved robustness and compensation for environmental disturbances and/or parameter ***,the controller can reduce the need for manual *** controller applies nonlinear generalized predictive control to generate an adaptive control signal for attaining robust performance.A wavelet-based neural network model is adopted as the prediction model with high prediction precision and time-frequency localization *** training is utilized to predict uncertain system dynamics by tuning the wavelet neural network parameters and the controller parameters *** performance of the controller algorithm is verified by both simulation,and in a real-time practical application involving a single-input single-output double-zone sliver drafting system used in textiles *** the simulation and practical results demonstrate an excellent control performance in terms of the mean thickness and coefficient of variation of output slivers,which verifies the effectiveness of this approach in improving the long-term uniformity of slivers.

关键词： Continuous material processing wavelet neural network(WNN) nonlinear generalized predictive control(NGPC) auto-leveling system

Classification and Gradation of Cultivated Land Quality in Bishan County of Chongqing, China

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Chinese Geographical Science 2007年第1期17卷 82-91页

作者： shao Jing＇an GE Xiaofeng WEI Chaofu xie Deti College of Resource and Environment Southwest Agricultural University Chongqing 400716 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China）

The conflicts among food security, economic development and ecological protection are the “sticking point” of undeveloped southwestern mountainous areas of China. The objectives of this study are to identify appropriate inte- grated indicators influencing the classification and gradation of cultivated land quality in the southwestern mountainous area of China based on semi-structure interview, and to promote the monitoring of cultivated land quality in this region. Taking Bishan County of Chongqing as a study case, the integrated indicators involve the productivity, protection, ac- ceptability, and stability of cultivated land. The integrated indicators accord with the characteristics of land resources and human preference in southwestern mountainous area of China. In different agricultural zones, we emphasize different indicators, such as emphasizing productivity, stabilization and acceptability in low hilly and plain agricultural integrative zone (LHP-AIZ), protection, productivity and stability in low mountain and hill agro-forestry ecological zone (LMH-AEZ), and acceptability in plain outskirts integrative agricultural zone (PO-IAZ), respectively. The pronounced difference of classification and gradation of cultivated land, regardless of inter-region or intra-region, is observed, with the reducible rank from PO-IAZ, LHP-AIZ to LMH-AEZ. Research results accord with the characteristics of assets management and intensive utilization of cultivated land resources in the southwestern mountainous area of China. Semi-structure interview adequately presents the principal agent of farmers in agricultural land use and rural land market. This method is very effective and feasible to obtain data of the quality of cultivated land in the southwestern mountainous area of China.

关键词： cultivated land classification cultivated land gradation semi-structure interview Bishan County

Effects of Land Management Practices on Labile Organic Carbon Fractions in Rice Cultivation

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Chinese Geographical Science 2009年第3期19卷 241-248页

作者： shao Jing＇an LI Yangbing WEI Chaofu xie Deti College of Geography Science Chongqing Normal University Chongqing 400047 China College of Resource and Environment Southwest University Chongqing 400716 China

A research trial with four land management practices, i.e., traditional tillage-fallow (TTF), traditional tillage-wheat (TTW), conservation tillage-fallow (CTF) and conservation tillage-wheat (CTW), was sampled in the 15th year after its establishment to assess the effects of different management practices on labile organic carbon fractions (LOCFs), such as easily oxidizable organic carbon (EOC), dissolved organic carbon (DOC), particulate organic carbon (POC) and microbial biomass carbon (MBC) in a typical paddy soil, Chongqing, Southwest China. The results indicated that LOCFs were significantly influenced by the combination of no-tillage, ridge culture and crop rotation. And, different combination patterns showed different effectiveness on soil LOCFs. The effects of no-tillage, ridge culture and wheat cultivation on EOC, DOC, POC and MBC mainly happened at 0-10cm. At this depth, soil under CTW had higher EOC, DOC, POC and MBC contents, compared to TTF, TTW and CTF, respectively. Moreover, the contents of LOCFs for different practices generally decreased when the soil depth increased. Our findings suggest that the paddy soil in Southwest China could be managed to concentrate greater quantities of EOC, DOC, POC and MBC.

关键词： no-tillage rice-wheat rotation ridge culture labile organic carbon fraction rice cultivation

AN INSIGHT ON DRIVERS OF LAND USE CHANGE AT REGIONAL SCALE

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Chinese Geographical Science 2006年第2期16卷 176-182页

作者： shao Jing-an WEI Chao-fu xie De-ti College of Resource and Environment Southwest University Chongqing 400716 P. R. China Chongqing Key Laboratory of Digital Agriculture Chongqing 400716 P. R. China

The studies of driving forces of regional land use change (LUC) are to reveal the real motivation behind the LUC and its interacting mechanism, so as to simulate and predict the process of LUC. Presently, studies rooting from different natural and socio-economic backgrounds and from different scales have deepened the people’s understanding and cognition to driving forces of regional LUC. Biophysical driving forces are relatively stable, and have the cumulating effects. Human driving forces are relatively active, and are main driving forces of short-term regional LUC. Existing regional LUC models can answer the three main problems: which contribution (why), which location (where) and what rate (when). But, regional land use system is defined as the self-organized system, usually affected by the cri- tical value area and sudden change, and controlled by different stages. To reduce the impact of critical threshold and break on land use system, the studies of LUC driving forces will aim at following priority areas: data linkage between remote sensing and no-remote sensing data; underlying driving force identification; driving factor quantification; driving factor scale dependence; and driving process integration simulation.

关键词： land use change driving forces driving mechanism process simulation regional scale

Sea surface temperature variations in the southwestern South China Sea over the past 160 ka

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Acta Oceanologica Sinica 2007年第2期26卷 49-55页

作者： xie Hongqin JIA Guodong PENG Ping＇an shao Lei State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China

Sea surface temperatures （SSTs） in the southwestern South China Sea have been reconstructed for the past 160 ka using the U37^k paleothermometer from the core MD01 - 2392. The temperature differences between glacial times （ MISs 6 and 2） and interglacial times （ MISs 5.5 and 1） are 2.2 ～ 2.5 ℃. Younger Dryas event during the last deglaciation was documented in both the planktonic foraminiferal δ^18 and SST records. After MIS 5.5, SSTs displayed a progressive cooling from 28.6 to 24.5 ℃ culminating at the LGM. During this gradual cooling period, warm events such as MISs 5.3, 5.1 and 3 were also clearly documented. By comparison of SST between the study core and Core 17954, a pattern of low or no meridional SST gradients during the interglacial periods and high meridional SST gradients during the glacial periods was exhibited. This pattern indicates the much stronger East Asian winter monsoon at the glacial than at the interglacial periods. Spectral analysis gives two prominent cycles：41 and 23 ka, with the former more pronounced, suggesting that SSTs in the southern SCS varied in concert with high-latitude processes through the connection of East Asian winter monsoon.

关键词： sea surface temperature alkenone Late Quaternary South China Sea East Asian monsoon

Efficient large-area flexible organic photovoltaic modules on transparent thin silver electrodes

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Science China Chemistry 2025年

作者： Cong xie Zedong Xiong Xinlu Liu Wen Wang Yang Liu Xueshi Jiang Xin Lu Lulu Sun Yinhua Zhou Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Kunming Institute of Physics

Large-area flexible organic photovoltaic（OPV） modules are challenging to achieve high power conversion efficiency（PCE）.Electrical shunts or shortages generally occur in large-area OPV modules due to the ultrathin（100–200 nm） and soft active layers. Improving the surface smoothness of bottom transparent electrode will be able to suppress the shunts and shortages. In this work, we report a method to fabricate smooth and flexible transparent electrodes based on thin silver film, and further to fabricate efficient large-area flexible OPV modules. The fabricated thin silver transparent electrodes simultaneously have high conductivity, high optical transmittance, good mechanical flexibility and low surface roughness. Humidity exposure（h.e.）treatment on MoO3effectively facilitates the continuous growth of the thin transparent silver electrode. 6 nm silver film on MoO3（h.e.） on plastic substrate shows a transmittance up to 89%, a sheet resistance of 15 Ω/sq, and a low surface roughness with a rootmean-square value of 0.276 nm. Furthermore, 52-cm2flexible organic solar modules（15 subcells） showed a certified PCE of12.66%. Furthermore, a 1350 cm2flexible component assembled by 25 pieces of 52–55 cm2modules showed certified PCE of12.10% with an open-circuit voltage of 62.85 V.

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Prediction and analysis of the potential risk of sudden oak death in China

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Journal of Forestry Research 2019年第6期30卷 2357-2366页

作者： Bo xie Chunxiang Cao Wei Chen bing Yu State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100101People’s Republic of China University of Chinese Academy of Sciences Beijing 100094People’s Republic of China School of Civil Engineering and Architecture Southwest Petroleum UniversityChengdu 610500People’s Republic of China

Sudden oak death(SOD)is one of the most rapid and destructive forest pathogens,which has caused the death of many host plants in Europe and *** are currently no cases in China where there are more host plants and a more suitable climate for this pathogen to ***,it is vital to discern the potential suitable habitat,quantify the risk levels,and monitor the potential high-risk *** this study,we modelled the potential invasion range and risk level of this pathogen at present and in future scenarios in China,using the least correlated components of all the environmental factors based on the Genetic Algorithm for Ruleset Production niche model and GIS *** results indicate that most areas in China are free from a potential SOD risk,and the majority of potential occurrence areas are concentrated in Southern China(Yunnan,Sichuan,Guizhou,Chongqing,Hunan,Fujian).The area of high and extremely high risk in 2050(RCP26,RCP45,RCP60,and RCP85)is larger than that at *** most susceptible area is Yunnan province with 80%of the area prone to SOD at extremely high risk in present and future *** results will be important for monitoring potential high-risk areas in the currently uninfected parts of China.

关键词： Phytophthora ramorum GARP Ecological niche models Suitable habitat Risk level

Structures, Stabilities and Work Functions of Alkali-metal-adsorbed Boron α1-Sheets

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Chemical Research in Chinese Universities 2017年第4期33卷 631-637页

作者： YI Tingting ZHENG bing YU Haitao xie Ying Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Science Heilongfiang University Harbin 150080 P. R. China

In this study, we employed the density functional theory method to simulate Li-, Na- and K-adsorbed boron α1-sheets（al-BSTs）. After optimizing possible structures, we investigated their thermodynamic stabilities, barriers for metal atom diffusion on the substrate, and work functions. The computed results indicate that the work function of α1-BST decreases significantly after the adsorption of Li, Na and K. Furthermore, under high hole coverage, these alkali-metal-adsorbed α1-BSTs have lower work functions than the two-dimensional materials of greatest concern and the commonly used electrode materials Ca and Mg. Therefore, the Li-, Na- and K-adsorbed α1-BSTs are potential low-work-function nanomaterials.

关键词： Boron α1-sheet Binding energy Migration barrier Alkali metal adsorption, Work function

Applicability of Artificial Recharge of Groundwater in the Yongding River Alluvial Fan in Beijing through Numerical Simulation

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Journal of Earth Science 2014年第3期25卷 575-586页

作者： Qichen Hao Jingli shao Yali Cui Zhenhua xie School of Water Resources and Environment China University of Geosciences Beijing Institute of Hydrogeology and Engineering Geology

A groundwater transient flow model was developed to evaluate the applicability and effectiveness of artificial recharge scenarios in the middle-upper part of the Yongding River alluvial fan in Beijing. These scenarios were designed by taking into account different types of recharge facilities and their infiltration rate with the Middle Route Project for South-to-North Water Transfer（MRP） as the recharge water source. The simulation results suggest that：（1） the maximum amount of artificial recharge water, for scenario I, would be 127.42×106 m3 with surface infiltration facilities; and would be243.48×106 m3 for scenario II with surface infiltration and recharge wells under the constraint of the upper limit of groundwater;（2） with preferred pattern of recharge facilities, groundwater levels in both optimized recharge scenarios would not exceed the upper limit within the given recharge period; and（3implementation of the recharge scenarios would efficiently increase the aquifer replenishment and the groundwater budget will change from-54.11×106 to 70.89×104 and 183.36×104 m3, respectively. In addition, under these two scenarios groundwater level would rise up to 30 and 34 m, respectively, without increasing the amount of evaporation. The simulation results indicate that the proposed recharge scenarios are practically feasible, and artificial recharge can also contribute to an efficient recovery of groundwater storage in Beijing.

关键词： groundwater modeling artificial recharge infiltration rate groundwater management.